Characterization of UV-Visible Aerosol Absorption Properties Using Satellite-Ground Synergy

Constraining spectral-aerosol absorption in remote sensing and modeling remains a challenging task. In this research, we retrieve wavelength-dependent single scattering albedo (SSA) of aerosols from UV to the visible range by using independently measured aerosol optical depth (AOD) from ground-based Sun Photometers at the Aerosol Robotic Network (AERONET) sites as a constraint in the inversion with measured satellite radiances. We utilize the near-UV (340, 354, and 388 nm) and visible (466 and 646 nm) radiances measured by the Ozone Monitoring Instrument (OMI) and MODerate Imaging Spectrometer (MODIS), respectively, for the proposed inversion. The wavelength-dependent single scattering albedo of aerosols is derived for a total of 96 sites distributed globally for which continuous, long-term AERONET measurements are available. The UV-Visible spectral dependence of SSA obtained from our application is found to be consistent with previous studies. In comparison to the AERONET, our retrieved SSA for 40% (60%) of observations at 388 nm and 646 nm agrees within the absolute difference of 0.03 (0.05) at 440 nm and 675 nm respectively. We will present seasonal behavior of spectral SSA over several regions worldwide influenced by the biomass burning, dust transport, and urban-industrial pollution. The derived aerosol spectral SSA data set extends the aerosol absorption record in the near-UV region, where such inversion from AERONET is non-existent.